Assembly or Optimized C for Lightweight Cryptography on RISC-V?

Abstract

A major challenge when applying cryptography on constrained environments is the trade-off between performance and security. In this work, we analyzed different strategies for the optimization of several candidates of NIST's lightweight cryptography standardization project on a RISC-V architecture. In particular, we studied the general impact of optimizing symmetric-key algorithms in assembly and in plain C. Furthermore, we present optimized implementations, achieving a speed-up of up to 81% over available implementations, and discuss general implementation strategies.

Status report on the second round of the NIST lightweight cryptography standardization process

“…Campos et al [265] compared the effectiveness of various optimization methods on six of the second-round candidates when implemented on RISC-V platforms. The focus of this work was not to compare the performance between candidates, but, rather, to compare different implementation optimization strategies of a small number of candidates.…”

Optimized Implementation of PIPO Block Cipher on 32-Bit ARM and RISC-V Processors

“…As a result of comparison with the implementation with Cortex-M4, RISC-V has about twice as general-purpose registers as Cortex-M4, but the efficiency of barrel-shifter is higher in terms of implementation speed for block cipher and hash function; therefore, It proved that RISC-V difficult to catch up Cortex-M4, using only 32RVI. In [34], an implementation study was conducted on the algorithm for LWC competition using RV32I. In their research, 32RVI and assembly characteristics were mainly used, not the algorithm itself.…”

Mod-k-Chained Variant of PRESENT and CLEFIA Lightweight Block Cipher for an Improved Security in Internet of Things

“…2.One area of the cryptography deals with the cryptanalysis of developed or improved ciphers. Differential [26] and Linear Cryptanalysis [27] has been the basic and first analysis of DES block cipher. [28][29][30][31][32][33] are the cryptanalysis frameworks and cryptanalysis work of well-known lightweight block ciphers.…”

“…Differential analysis is the cryptanalysis technique that studies the strength of cipher against differential attacks. Differential analysis is designed by Biham and Shamir [26]. It is used to trace the difference in outputs through non-linear parts of a block cipher.…”

“…LWC includes many mechanisms like PRESENT, CLEFIA, SIMON, SPECK, SKINNY, ZORRO, HIGHT, XTEA, encoder-based, cellular-automata-based, bit-permutation-based, etc. [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29]. In past years, the community of lightweight cryptography has developed many mechanisms suitable for IoT and other similar environments.…”